A. If a

LiveData

object returns a non-null type would it at all trigger an observer's

onChange()

if there is no data to be served?

val someLiveData: LiveData<List<String>> = ...
val someObserver = { someValue: String ->
    // Will this return only if there is non-null data in someLiveData
}

B. Same case as above except the observer class expects a nullable type. So if

LiveData

returns non-null type but the observer object expects a nullable type then would we get a null value when there's nothing to be returned?

val someLiveData: LiveData<List<String>> = ...
val someObserver = { someValue: String? ->
   // Will this return null value from a non-null LiveData
}

i seem to have managed to break

:app:compileDebugUnitTestKotlin

file or directory '/Users/robmunro/repos/personal/cuer/cuer/app/src/testDebug/kotlin', not found

file or directory '/Users/robmunro/repos/personal/cuer/cuer/app/src/testDebug/java', not found file or directory '/Users/robmunro/repos/personal/cuer/cuer/app/src/testDebug/java', not found file or directory '/Users/robmunro/repos/personal/cuer/cuer/app/src/testDebug/kotlin', not found file or directory '/Users/robmunro/repos/personal/cuer/cuer/app/src/testDebug/java', not found file or directory '/Users/robmunro/repos/personal/cuer/cuer/app/src/testDebug/java', not found Transforming YouTubeAndroidPlayerApi.jar with JetifyTransform Transforming YouTubeAndroidPlayerApi.jar with IdentityTransform Transforming YouTubeAndroidPlayerApi.jar with JetifyTransform Transforming YouTubeAndroidPlayerApi.jar with IdentityTransform Using Kotlin/JVM incremental compilation file or directory '/Users/robmunro/repos/personal/cuer/cuer/app/src/test/kotlin', not found file or directory '/Users/robmunro/repos/personal/cuer/cuer/app/src/test/kotlin', not found file or directory '/Users/robmunro/repos/personal/cuer/cuer/app/src/test/kotlin', not found i: found daemon on port 17524 (224945 ms old), trying to connect i: connected to the daemon Options for KOTLIN DAEMON: IncrementalCompilationOptions(super=CompilationOptions(compilerMode=INCREMENTAL_COMPILER, targetPlatform=JVM, reportCategories=[0], reportSeverity=2, requestedCompilationResults=[0]kotlinScriptExtensions=[kt, kts, java, java, java]), areFileChangesKnown=false, modifiedFiles=null, deletedFiles=null, workingDir=/Users/robmunro/repos/personal/cuer/cuer/app/build/kotlin/compileDebugUnitTestKotlin, multiModuleICSettings=MultiModuleICSettings(buildHistoryFile=/Users/robmunro/repos/personal/cuer/cuer/app/build/kotlin/compileDebugUnitTestKotlin/build-history.bin, useModuleDetection=true), usePreciseJavaTracking=trueoutputFiles=[/Users/robmunro/repos/personal/cuer/cuer/app/build/tmp/kotlin-classes/debugUnitTest, /Users/robmunro/repos/personal/cuer/cuer/app/build/kotlin/compileDebugUnitTestKotlin]) AAPT2 aapt2-7.0.0-beta04-7396180-osx Daemon #0: shutdown <============-> 98% EXECUTING [4h 43m 44s]

IDLE

IDLE

IDLE

:app:compileDebugUnitTestKotlin

Hey guys. I had that code

@Synchronized

fun abc() {

// do some heavy tasks in multiple threads

}

In the document `@Synchronized`is thread safe annotation but I wonder that Should I use multiple thread operations inside function

abc()

?

Can someone invite me to the AV channel？

Presumably it would be unsafe to launch a coroutine using

lifecycleScope

in an activity's

onDestroy()

since the scope only spans until

onDestroy()

is called, right? What would be a suitable alternative to launch a coroutine to do some kind cleanup job that shouldn't be immediately canceled when the activity is destroyed?

MainScope

?

Hey guys, I need help. I am new to kotlin, what is the best way to store authentication token for a user in an app.

Hi everyone, Does anyone have trouble importing "import androidx.compose.material.LocalContentAlpha" or maybe there is another way to implement

CompositionLocalProvider(LocalContentAlpha provides ContentAlpha.medium) {
    Text("3 minutes ago", style = MaterialTheme.typography.body2)
}

i have string 

<string name="data">%1$s / %2$s</string>

 i pass

varargs

in function like that

fun getText(varargs text: String){
	getString(R.string.data,text)
}

I called function

getText("1" ,"2")

It gives error 

E/AndroidRuntime: FATAL EXCEPTION: main

  

Process: com.vivek, PID: 5126

  

java.util.MissingFormatArgumentException: Format specifier '%2$s'

    

at java.util.Formatter.format(Formatter.java:2529)

    

at java.util.Formatter.format(Formatter.java:2459)

    

at java.lang.String.format(String.java:2911)

Hi, Can anyone give me and example of using Channel with suspendCancellableCoroutine, for observing firebase document updates

hi, Best sdk for video calling in android for kotlin?

Hi, I am having some problems with Hilt dependency injection. If I clean the project and then build, it builds just fine. But gives me ‘Unresolved reference’ on a bunch of my injected view models if I change anything in my activities/fragments and try and build again without cleaning. I have tried all different kinds of configurations in my gradle files, to no avail, me configuration looks like this:

Hi, I am trying to fetch JSON data from an API in my kotlin android project. I tried researching about it but was unable to find a direct and easy method. Can anyone help me regarding the same? I am trying to get the City Name and Temperature only.

Hi guys! I found this issue while using Koin with JetpackCompose and create feature request on github. We can discuss it here to be more productive

Hey guys, I have an app that has nested nav graph navigation setup. The root host seems to be setting a global theme for the rest of the graphs. E.g a theme set in the root navs activity is set in all other nav graphs activities. Has any one faced this issue and how did they go about solving it?

would it be possible, to start activity for result (e.g. select file), if you only have context. I have a wild idea of making interactor/usecase that does that. Any ideas?

class SelectFileUseCase @Inject constructor(
    @ApplicationContext private val context: Context
) {
    operator fun invoke(): Uri {
        val intent = Intent().apply {
            type = "file/*"
            action = Intent.ACTION_GET_CONTENT
            addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
        }

        context.startActivity(intent)
        
        // how to get result??
        context.registerReceiver(receiver, filter) // maybe?
    }
}

Is it possible to specify the underlaying

Map

implementation of

mutableStateMapOf()

?

Hi, for location tracking in background which one is good ? Work Manager or Service or JobScheduler or something else?

Hi, Wich is the best way to use Hilt with Mavericks viewmodel ?

While I understand the need for limiting the discussion here to "Using Kotlin to build Android applications" (and I deleted my previous message - I'm sorry), in my experience, "Android United" and "Android Chat" are almost dead. I still get more help in the #android-dev IRC channel on libera.chat. StackOverflow is way more useful than all those sources together, even if the kind of interaction is different from a chat. I'll try the Discord server, in future.

does jetpack compose support kotlin compiler version 1.5.*??

So it looks like android can swap out dex files at runtime via the DexClassLoader. React Native allows downloading new code and swapping it out, which seems like a great way to force updates for an app. Why aren't their libraries for this on Android? This seems very useful. Is there something I'm not realizing?

Am using

androidx.datastore:datastore-preferences:1.0.0-rc01

and seeing occasional crashes in play console (stack trace in thread) but can't reproduce locally....just in case anyone else has encountered this.

Hi everyone Today I've published an article about how you can protect your Android app from being tampered. You can check it out at https://funkymuse.dev/posts/android_anti_tampering/

Hi there ! I want to create this, I try to explore some thing about Round ProgressBar Segment, but Im sill fail because some article is not detail. Anyone can help me. Im not good at CustomeView

Hello,  I want get the objects from users array from API using Moshi , but I get this error  'Expected BEGIN_ARRAY but was BEGIN_OBJECT at path $'. What mistake I made? Thanks in advance.

{
  "users": [
    {
      "id": "1",
      "name": "Bill Roy",
    },
     {
      "id": "2",
      "name": "Ben Bush",
    },
    {
      "id": "3",
      "name": "Dan Fox",
    },

  ]
}

User.kt

data class User(
    @Json(name = "id")
    val id: Int = 0,
    @Json(name = "name")
    val name: String = "",
    @Json(name = "users")
    val userList: List<User>
)

ApiService.kt

interface ApiService {
    @GET("getUsers")
    suspend fun getUsers(): Response<List<User>>
}

Hello guys!.. I need your help. I need to pass parameter to the composable inside sealed class. Below is the screenshot where there is RecommendedScreen(models = ) composable that needs a parameter. Can you guys tell how to do that?.

Does anyone know how to do like this Search in instagram and show images like this??? Images coming from server.

Android Studio 2020.3.1 Canary 15 supports databinding with StateFlow<T> in viewmodels. Does it support two-way databinding when the view property is also a StateFlow<T>? If now, why?